I disagree. There were sneak attacks long before 'WMD's existed. The principle is that if the President can invade a nation (or authorize any other military action on foreign soil) because he sees the current situation in that nation as a threat (or future threat), he may also do so merely by declaring this threat to exist whether or not it really does. This is applicable to any war and always will be. I would disagree with the original statement by Lincoln (maybe it's a little out of context), although I also think it's necessary for the President to have a greate deal of evidence to support any decision of this kind.
I think you are forgetting that Bush did not decide to invade Iraq on his own authority. He went to Congress and got its authorization, as the Constitution called for him to do.
I also find it difficult to imagine that any American would expect the President to allow a nuke to be detonated in America because it wouldn't be sporting to strike first.